Engine starting mechanism



Feb. 14, 1933.

D. P. KEARNEY ENGINE STARTING MECHANISM Filed Ma 9, 19:52

INVENTOR Kearney A TTORNE y Patented" Feb. 14, 1933 UNETED STATES PATENT OFFICE mm I. mm, 6! MY MICHIGAN; ASSIGNOB T ECLIPSE MACHINE comm, 0E NEW YORK, A. CORPORATION OF NEW YORK ENGINE STARTING MMHARISM Application f led Icy 9,

This invention relates to on ice starting mechanism and more particular y to the type of starting mechanism which a drivin member is automatically traversed into an out of engagement with an engine member and rotated to crank the engine.

In some installations of this type, the driving member occasionally fails to traverse into mesh with the engine member due to an aclo emulation of dirt, rust, or grease or other causes. It is thereforemn ohject of this invention to provide an engine starter of the above type, embodying novel means to auto matically insure traversal of the driving member into driving relation with the engine member.

p A further object of-this invention is to provide such a device embodying an automatically controlled detent to cooperate with the driving member and assist traversal thereof upon actuation of the starter.

Another object of the invention is to provide such a device in which the detent con trols the driving member during initial actuation of the starting mechanism and there after is rendered inoperative in order to prevent interference with the demeshing action thereof.

Another object of the invention is to provide such a device in which the detent controls the driving member during initial actuation of the starting mechanism and there after is rendered inoperative responsive to rotation of the engine in order to prevent interference with the demeshing action thereof. 7

Another ohjcct is to provide such a device embodying an. electricallymontrclled detent.

which normally cooperates with the driving nemlzcr to keep it rotationally stationary while said member is being traversed toward the engine member upon closure of the starting circuit and thereafter is rendered inoperative until the circuit is again opened.

.A further object to provide such a device embodying a time delay in connection with. the detent for preventing said detent from rotor-nin to a normal operative posh tion for a predetermined time after the de- B382. Serial Ito. 810,185,

tent controlling means has become ineffec- It is another object to provide such a device which is readily adaptable to commercial types of starters and maybe positioned in various relations thereto without effecting its efficiency or reliability.

It is; a further object of the invention to provide such a device which is reliable in operation, cheap in construction, and adjustable tothe varying conditions of engine operation:

Further objects and advantages will be apparent to those skilled in thisart from the' following description and accompanying drawing in which:

Fig. 1 is a side elevation partly in section of one preferred embodiment of the invention, the parts being shown in normal or idle position;

Fig. 2 is a view similar to Fig. 1' illustratin another embodiment of the invention.

eferring first to Fig, 1 of the drawing, there is illustrated a power member 1 which may be the extended armature shaft of an electric motor now shown, and a drive head 2 suitably fixed thereon as by means of a key 3 and anchoring stud 4. An operating member in the form of a screw shaft 5 is slidahly journalled on the power shaft 1 and has a yielding driving connection thereto in the form of a coiled driving spring danchored to the drive head and to said screw shaft as by means ofanchoringstuds 4 and 7 respectively. 1.

5 driving member in the form of a pinion 8 is threaded on the screw shaft 5 whereby relative rotation therebetween causes automatic traversal of the pinion into or out of engagement with a member of an engine to be started such as a flywheel gear 9. Traversal of the pinion into mesh with the flywheel gear islimited by suitable stop means such as a stop nut 11 on the screw shaft in the path of said pinion whereby further rotation of the screw shaft in the meshing direction as; indicated by the arrow is transmitted to the pinion to crank the engine.

According to the present invention means are provided for insuring the automatic traversal of the pinion 8 into mesh with the engine gear 9 in the form of a detent for restraining rotation of the pinion upon initial actuation of the screw shaft, said detent being so arranged and controlled as not to interfere with the free rotation of the pinion during cranking or with the demeshing action thereof. As shown in Fig. 1 this detent is in the form of an elastic friction shoe 12 carried by a rod 13 which is slidably mounted in. the end of a cylinder 14, said cylinder being suitably mounted on a housing 15 for the starter drive in such a position that the rod 13 extends within said hous ing with the shoe 12 in position to bear on a flange 16 of the pinion 8 when the latter is in idle position. Means are provided for normally yieldably pressing the shoe 12 the desired time delay.

In the operation .of this embodiment of against the flangelG in the form of a spring 17 within the cylinder 14 bearing on a head" 18 fixed on the rod, inward movement of the rod being suitably limited as by means of a flange 19 thereon. i

In order to prevent the detent from bearing on the pinion during'the cranking action,

the shoe 12 is formed to engage the flange 16 only until the pinion has come into. initial meshing engagement with the engine gear, the further meshing movement 0 the pinion causing disengagement from the detent. In order to prevent interference of the de tent with the demeshing action of the pinion, means are provided for withdrawing the detent from operative position responsive to rotation of the engine. For this purpose any engine operated source of power such as intake vacuum, exhaust pressure, or an engine driven'pump or generator may be used. As here illustrated this means is provided by of the pinion. For this purpose the lower end of cylinder 14' is provided with an inlet 23 controlled by a check valve 24 for allowing rapid withdrawal of the piston 18, while a bleeder opening 25 is arranged to control the return movement of the piston to'secure the invention energization of the starting motor causes-rotation of the screw shaft 5 in the direction of the arrow; Rotation of the pinion 8 therewith is resisted by the detent 12as well as by its own inertia, whereby aeeaeee the pinion is traversed into mesh with the fiy-wheel gear. Meshing of the pinion is thus insured by contact of the detent on the pinion member until said pinion is well into mesh with the flywheel gear. Further rotation of the screw shaft 5 after the pinion has engaged the stop nut 11 causes the engine to be cranked in the usual way. I

As soon as an appreciable vacuum is estab, lis'hed by the turning over of the engine, thepiston 18 is actuated to retract the detent from operative position, the check valve 24: opening to allow this action, and said detent is maintainedin retracted position as long as the engine remains. self-operative. When the engine stops, the air below the piston 18 is trapped by said check valve and forced to escape through the bleeder 25. The return of the detent to operative position is thus retarded as above set forth.

Referring now to Fig. 2 of the drawing,-

the parts of the starter drive and detent therefor are similar in arrangement to Fig. l and are correspondingly numbered. In this embodiment of the invention, however, electro-magnetic means energized from the starting circuit are usedto control the detent 12. As here shown, this controlling means or mprises a magnetic plunger 26 suitably fixed to the detent rod 13 and a coil 27 surrounding said plunger and adapted when energized to attract said plunger toward a fixed pole piece 28. The coil 27 is placed in series in the starting circuit comprising a battery 29 grounded at 30 and connected by alead 31, starting switch 32 and the lead 33 to'one terminal of said coil. The opposite terminal is connected by a lead 3 to a startingmotor SM which is grounded at 35 to complete the starting circuit. 4

The coil 27 and spring 17 are suitably de signed so that a. proper balance of forces is established, permitting withdrawal, of the plunger..,.vvhen' the starting motor cranking current is near its maximum flux. Spring 17, is, however, made of suflicient. stiffness to prevent retraction of the plunger until the starting motor circuit is near its maximum cranking flux, at which time magnetic plunger 2 moves into contact with stationary pole piece 28 thus completing the magnetic cir cuit. Since the holding effect on magnetic plunger 26 is increased by the closure of the magnetic circuit, the current in the starting circuit is sufiicient to hold the detent retracted under all conditions until the starting I switch 32'is opened.

I In the operation of this embodiment of the lnvention and starting with the parts in.

the positions illustrated, closure of the starting switch 32 causes energization of the starting motor SM to cause the pinion 8 to engage and crank the engine as above set forth. Upon initial closure of the starting switch,

the coil 27 is energized to some extent, but

- ber of an engine to be started, a yielding the current a'ssing through said coil during traversa of the pinion is not of sumcient strength and duration to retract the lunger 26to inoperative position a ainst the orce of spring 17. When the starting motor picks up the load of cranking the engine, however, the cranking current renders the coil 27 effective to overcome spring 17 and move plunger 26 into contact with stationary pole piece 28. When the magnetic circuit has thus been closed, the reluctance thereof is reduced whereby the coil 27 is enabled to hold the detent retracted even when the current is diminished by the release of the load on the starting motor as the engine starts. It will thus be seen that the detent is effective during traversal of the pinioninto mesh with the engine member but is rendered inoperative during cranking of theengine and remains inoperative as long asthe starting circuit is closed.

When the starting switch 32 is opened by the check valve 24 and bleeder opening 25 functions to prevent the premature return of the detent to operative position as above described.

Although but two embodiments of the invention have been shown and described in detail, it will be understood that these em bodiments are not exclusive and other embocliments are possible and various changes may be made in the arrangement and construction of the parts without departing from the spirit of the invention as defined in the claims appended hereto.

What isclaimedis: 1

1. In an engine starter, an operating memher, a driving member, said members having connecting means whereb relative rotation causes translation of the riving member into or out of engagement with a member of an engine to be started, means for op osing rotary movement of the driving mem r to insure its traversal into engagement with the engine member, means for rendering said opposing means inoperative to oppose. traversal of the driving member out of driving osition when the engine starts, and means ibr delayingthe restoration of the opposing means for a predetermined time.

2. In an engine starter, an operating member, a driving member, said members having connecting means whereby relative rotation causes translation of the drivingmemher into or out of engagement with a meanetent for opposing rotary movement 0 the driving member to insure. its traversal into engagement with the engine member, means signed my name.

said detent to operative position.

4. In an engine starter, a screw shaft, a pinion threaded thereon for movement into and out of engagement with an engine gear, a detent normally opposing rotation o the pinion, means responsive to rotation of the engine for retractin said detent and means for maintaining sai detent retracted until after the starting motor shall have come to rest. the operator, the timedelay means mcluding 5. In an engine starter, a screw shaft, 8. pinion threaded thereon for movement into and out of engagement with an engine ear a detent normally opposing rotation of t e inion, pressure pro ucing means operate by the engine, means operated by said pressure producing means for retractin said detent, and means for maintaining said detent retracted until after the engine comes completeliv to rest.

6. n an engine starte a screw shaft, a pinion threaded thereon tor movement into and out of engagement with an engine gear, a

detent normally opposin rotation of the pinion, means energized y cranking'current for withdrawing said detent and holding it retracted as long as the starting motor is energized. I

7. A starting mechanism for internal combustion engines having a rotatable shaft and a driving "member mounted thereon for longitudinal movement thereof and rotary movement therewith and adapted to enga e -a member of the engine to be started, a e:

tent normally cooperating with a portion of the driving member to insure traversal of said driving member into driving relation with said engine member, power-operated meansfor disengaging said detent when said engine becomes self-operative, and time delay means preventin reengagement of the detent and drive mem r until a predetermined time after said power-operating means ceases .to be effective. 7

In testimony whereof, I have hereunto DANIEL 1P. KEARNEY.

for withdrawing said detent when the engine starts, and means fordelaying the return movement of the detent to operative position.

3. In an engine starter, an operating mem- 

